13×3 ft run, should i make it bigger?

[Tango Charlie]

Yes, go bigger - or more precisely, wider, if possible. A narrow run can cause behavioral problems just as a small one would, as it does not allow for chickens with pecking order problems to safely pass by one another.

^ I agree with this. I solve every problem by projecting the information to extremes. E.g. if this run was 48' long by 1' wide, it'd be maddening. So, maybe back off the long and skinny proportions.